[QUOTE 4497729, member: 9609"]But on the very rare times I have been on a cycle path it has amazed me at the lack of keeping-to-the-left discipline, when you see someone coming the other way it seems to be a 50/50 whether they will move left of right.[/QUOTE]
I think I've shared the trick I use before, but here it is again: I put my left hand, open, palm forwards and fingers to the left, above the left top corner of my handlebars (so above hoods on drop bars, or above the bend on swept bars). I'm not sure why it works, but it does well over 95% of the time. When it's failed, it's usually on roadside tracks where a nervous/wobbly-looking salmoning* rider is determined to stay as far away from motor traffic as possible, but I did have one near-miss where a roadie is going a bit fast head-down on a quiet track and not looking as he rounded a blind bend in the middle of a narrow 2m-wide section - after how he swerved around the wet track when I rang my bell, I was impressed that he kept the rubber side down!
* salmoning is riding a track on the opposite side to the carriageway for their direction. Often perfectly legitimate, but tends to be riskier IMO because any motorists crossing the track tend to look right more (because that's where the nearest motor vehicles that can hurt them appear from).